The plasma membrane mainly contains lipids, proteins, and carbohydrates. Phospholipids make the bilayer of the plasma membrane. Carbohydrates can be found attached to proteins and lipids.
The carbohydrates that are attached to lipids are called phospholipids and those with proteins are called glycoproteins. mRNA is the molecule which is not the part of the plasma membrane. mRNA is produced in the nucleus through the transcription process and is responsible for proteins formation.
So phospholipids, glycolipids, and glycoproteins are the part of the plasma membrane but not messenger RNA.
The main component of the cell membrane are made of cholesterol and phospholipids. Carbohydrates might also be one of the components of plasma membrane.
A phopholipids is a lipid bylayer which is made of glycerol,phosphate linked head group and two fatty acid tails and a
Messenger RNA is not a component of the plasma membrane.
It is a semipermeable in nature because of its constituents.